Test Method


CPT Code

88342 x 1 or 88341 x 1 (qualitative)
88360 x 1 (quantitative, semi-quantitative - manual)

Stains / Test Description

MLH-1 [G168-15] recognizes human and mouse MLH-1 (80-85 kDa). MLH-1 antibody and MSH2 are involved in the DNA mismatch repair (MMR) process. Microsatellite instability (MSI) is an alteration of microsatellite repeats during DNA replication and is a hallmark of the inactivation of the MMR genes. These defects in MMR have been related to human carcinogenesis. Immunostaining for MLH-1 and MSH2 may be useful to aid in identifying the most probable gene responsible for the MSI. Studies have shown that the expression level of MLH-1 may be a survival indicator.

Specimen Requirements

(1) H&E slide with formalin-fixed, paraffin-embedded (FFPE) tissue, fixed with 10% NBF.
One (1) unbaked, unstained slide for H&E staining (required) and two to three (2-3) positively charged unstained slides (all cut at 4 microns) for each test/antibody ordered

Block and slide identifiers should be clearly written and match exactly with the specimen ID and specimen labeling as noted on the requisition.

Storage & Transport

Ship specimen same day (whenever possible) with refrigerated (not frozen) cold pack

Turnaround time

1-3 days depending on level of service

Level of Service

Global (with interpretation)
Slide Only (glass slides only)
Web-Enabled (glass and digital images through eCSI portal)